Orchestral effect producing system for an electronic musical instrument

ABSTRACT

An orchestral effect producing system for an electronic musical instrument comprising a first keyboard for a melody performance and a second keyboard for accompaniment to the melody performance on which several keys are normally operated at the same time. A keyer derives from tone generators tone signals corresponding to the simultaneously operated keys in response to key operations on the second keyboard. The tone signals thus generated are separately supplied to tone coloring filters having different frequency characteristics to obtain differently colored tone signals, thus furnishing a melody performance on the first keyboard with an orchestral accompaniment effect bearing the tone colors of various musical instruments.

United States Patent 11 1 TONE TONE COLORING GENERATORS FILTER KEYER lI 1111 3,749,807 Adachi July 31, 1973 ORCHESTRAL EFFECT PRODUCING 2,997,908 8/1961 1111116111 .Q 84/101 SYSTEM FOR AN ELECTRONIC MUSICAL 3 83 33 21:32; 3

, eyer INSTRUMENT 3,433,880 3/1969 Southard.. 84/l.17 [76] Inventor: Takeshi Adachi, 600-62 3,603,713 9/1971 Nakada 84/1.19

Tomitsuka-cho, Hamamatsw hi 3,610,804 10/1971 Matsuura 84/l.17 Japan 3,619,469 11/1971 Adachi 84/1.17 3,624,263 1 11/1971 Uchiyama 84/103 [22] Filed: Apr. 11, 1972 21 1 App], No; 242,917 Primary Examiner-Richard B. Wilkinson I 1 isria ymysyi i zitanley -..LWit!s9 wk 1. p A I Foreign Application Priority Data alorney Robert D Flynn, Stephen H Fnshang et Apr. 14, 1971 Japan 46/23630 9 July 2, 1971 Japan 46/48673 57 ABSTRACT 52 U.S. Cl 84/117, 84/1.19, 84/1 .21 chesml effect Pmducing System electmnic [51] Int. Cl. Gl0h 1/02 msical instrument comprising a first kgayboard for a [58] Field 61 Search 84/101, 1.11, 1.17 meldy Performalnce and sewnd keybwd 4/ 9 L22 L24, L03 DIG. 9 L12 L21 companiment t0 the melody performance on which several keys are normally operated at the same time. A [56] Reerences Cited keyer derives from tone generators tone signals corre- UNITED STATES PATENTS spending to the simultaneously operated keys in re- I sponse to key operations on the second keyboard. The 1(1); 2:52;; 84/ 1.01 tone signails thus generated are separately supplied to 1 3/1972 Adachi tone coloring filters havmg different frequency charac- 365903l 4/1972 Adachi teristics to obtain differently colored tone signals, thus 3:694:559 9/1972 Suzuki furnishing a melody performance on the first keyboard 2557133 6/1951 M n with an orchestral accompaniment effect bearing the 2,585,357 2/1952 Wayne tone colors of various musicalinstruments. 2,811,069 10/1957 Faulkner 84/101 19 Claims, 13 Drawing Figures COLORING PATENTED U 3 1 SHEEI 30F 7 21Aw F flflflfl 5 T 21B- ZIC'C I l 240 I i I l 1 l (L v 10 6 l {42m 428 42C 420* L E- J TONE COLORING FILTER 1 TONE COLORING FILTER I 11 F -o I TONE COLORING TONE COLORING FILTER 1v 1 F TONE'COLORING 43A 4 l FILTER I 24A/7K TONE COLORING J FILTER 11 TONE ,COLORING'ZBC :1

TONE COLORING I 4 FILTER IV FIG. 4A I.

F I G. 48

blmsoc TONE COLORING FILTER IV NLNQSOD SHEET l [IF 7 TONE COLORING FILTER n FILTER [[I TONE COLORING TONE COLORING FILTER ALTJ-SOA TONE COLORING *FILTER 11 ALAS-50B TONE COLORING TONE COLORING I FILTER TONE COLORING FILTER PAIENIEII I 3 I Im 23C\ ZICW 2IDo----I m2 w2 OZGDQOEOEE QZDOm OP I TONE COLORING /23B 24B TONE COLORING FILTER UPPER KEYBOARD CHANNEL S TONE COLORING KEYBOARD DETECTOR LOWER CHORD J mmotqmwzwo E s wzok PEDAL KEYBOARD CHANNEL-;-

' PMENIH] JUL 3 1 I973 I saw 5 or 7 col V99 LO PATENTEDJULBHBB sums UF 7 F I G. 7

CHORD DETSEZCTOR I 54m r-' i I 21A 23A i I 54A2 I I THIRD ----T-T GATE ESNE LORING MATR'X i FILTER I X I l l I 54C 1 5481. l I GATE FIRsT I T 3 TONE I MATR'X III I I 5482 COLORING GATE FILTER n i i) I TONE I I COLORING l I FILTER m I I I 210 230 I I i 230 I I I TONE I COLORING l.

FILTER m To SQUND REPRODUCING MEANS musical instrument using an orchestral effect produc- This invention relates to an electronic musical instrument provided with a first keyboard for a melody performance and a second keyboard for accompaniment to the melody performance and more particularly to an orchestral effect producing system for an electronic musical instrument capable of providing a melody performance with an orchestral accompaniment effect.

With a general electronic musical instrument, a melody is playedby the right hand and accompaniment thereto by the left hand. Accompaniment bythe left hand is a chord performance effected by simultaneously operating several keys. In this case, a prior art electronic musical instrument causes tone signals drawn out from the tone generators to pass through the identical tone coloring filters even when several keys are simultaneously depressed, thus imparting the like tone color to the tone signals. Moreover, the conventional electronic musical instrument is generally equipped with a plurality of tone color levers or stops having different characteristics. Even some of the levers or stops are simultaneously thrown, the tone coloring filter only changes its frequency characteristics. When, therefore, a plurality of tone signals are made to pass through the tone coloring filter, tone signals are only given the same tone color. Therefore, the prior art electronic musical instrument failed to impart different tone colors to the tone signals delivered from the tone generators by simultaneous operation of a plurality of keys, and in consequence to provide accompaniment to a melody performance with the ensemble effect of an orchestra. Accordingly, the object of this inventionis to provide an orchestral effect producing system for electronic musical instruments which is capable of imparting different tone colors to tone signals used for accompaniment to a melody performance.

SUMMARY OF THE INVENTION According to this invention, there is provided an 7 electronic musical instrument which comprises a first keyboard means having a plurality of keys for a melody performance; a second keyboard means having a plurality of keys for accompaniment to the melody performance, some of the keys being generally operated simultaneously; a plurality of tone generators for generating tone signals for the melody performance and accompaniment thereto, first keyer means coupled to the tone generators and first keyboard to derive tone sig nals from the tone generators upon key operation; first tone coloring filter means connected to the firstkeyer means; second keyer means coupled to the tone generatom and the second keyboard and having output c0n-, ductors for producing at the respective output conduc tors respective different tone signals corresponding to respectively different'onesof the simultaneously operated keys; a plurality of second tone coloring filter means connected to the output conductors of the second keyer means and having different frequency characteristics for providing the tonesignals with different tone colors; and sound reproducing means connected to the first and second tone coloring filter means.

The present invention can be more fully understood from the following detailed description when taken in connection with the accompanying drawings, in which:

of a preference circuit, to couple it to the succeeding "third keyer,l8. i

FIG. 1 is a schematic block diagram of an electronic.

ing system according to this invention;

FIGS. 2A, 2B and 2C represent concrete key switch arrangements used in the second keyer of FIG. 1;

FIGS. 3A and 3B show the concrete tone color selectors of FIG. 1; g y I FIGS. 4A and 4B illustrate modifications of the tone coloring filter of FIG. 1;

musical instrument using an orchestral effect producing system according to another embodiment of the ini 1 ,vention; v v FIG. 6 is a circuit diagram of the chord detector of FIG. 9 shows the concrete arrangement of the key controlled variable voltage source of FIG. 8.

Referring to FIG. 1, schematically showing the concrete arrangement of an electronic musical instrument using an orchestral effect producing system according to this invention, reference numerals ll, 12 and 13 respectively denote a right hand-operated upper or first keyboard used for a melody performance, a left hand operated lower or second keyboard used for a chord performance and a left foot-operated pedal keyboard used for a bass performance. For the object of this invention, it will be noted that the first and second keyboards represent not only the upper and lower keyboards of a multistage keyboard type electronic musical instrument, but also the right hand-operated melody performance section and the left hand'operated chord performance section of a single keyboard used in a singlekeyboard type electronic musical instrument.

Tone signals from the tone generators 14 are coupled to a first keyer 15 including key switches actuated by the keys of the first keyboard 11 and also to a second keyer 16 including key switches actuated by the keys of the second keyboard 12. On the second keyboard 12 adapted to play a chord performanceas accompaniment to a melody performance, there are generally operated a plurality of keys at the same time. The tone signals from the tone generators Mare further coupled to a third keyer 18 including key switches actuated by the keys of the pedal keyboard 13 through a single tone selecting memory circuit 17 operated under control of the keys. Even when there are depressed, for example, adjacent keys on the pedal keyboard 13, the single tone selecting circuit 17 selects and stores'a tone signal corresponding to one of the operated keys e.g., by means Tone signals keyed by the firstand third keyers l5 and 18 are supplied to tone coloring filters l9 and 20. The second keyer l6 operated under control of the second keyboard 12 delivers from the tone generators l4 tone signals corresponding to the simultaneously operated keys of the lower keyboard 12, and consequently is provided with output conductors 21A to 21D as many as or more than a maximum number of keys that can be operated at the same time. On the second keyboard 12 operated by the left hand for a chord performance, there are simultaneously operated four keys at most, so that the indicated four output conductors will practically serve the purpose. Of course, the number may be freely chosen.

Tone signals brought from the second keyer 16 through the output conductors 21A to 21D are supplied to a tone color selector 22, which in turn selectively couples the signals to the succeeding tone coloring filters 23A to 23D having the same number as the output conductors 21A to 21D. The tone coloring filters 23A to 23D are so designed as to provide tone signals supplied thereto with different tone colors, namely, those peculiar to various musical instruments. Output signals fro m the" tone coloringfilters 23A to 23D pass through variable resistors or level control means 24A to 24D to one end of a potentiometer 25, the other end of which is coupled to the output of the tone coloring filter 19 through a level control means 27. The slidable arm 26 of the potentiometer 25 is connected through an expression control 28 to a reproducing means including an amplifier 29 and loud speaker 30. The potentiometer 25 is intended relatively to vary the levels of tone signals conducted to the reproducing means for a melody performance and those for a chord performance. Output from the tone coloring filter is coupled to the slidable arm 26 of the potentiometer 25. Reference numeral 31 is an expression pedal for actuating an expression control 28 by the right foot.

FIGS. 2A to 2C illustrate the key switch arrangements embodying the second keyer 16 of FIG. 1. All these arrangements include four groups 40A to 40D of key switches to match the four output conductors 21A to 21D. In FIG. 2A, the key switches are connected in series so as to cause the nonnally closed fixed contact on one key switch of each group to be connected to the movable contact of the adjacent key switch on the lower pitch side. The four key switches of the respective groups are actuated by the corresponding keys of the second keyboard 12. The normally open fixed contacts of the key switches of one group are successively connected to the normally closed fixed contacts of the corresponding key switches of the adjacent group. The idle normally open fixed contacts of the key switches of the lowest group in FIG. 2A are connected to the corresponding tone generators. The idle movable contacts of the four key switches actuated by the keys of highest pitches on the extreme right-hand side are connected to the four output conductors 21A to 21D. Where, in FIG. 2A, four keys are operated at the same time, that of the tone generators corresponding to the operated keys which produces the lowest pitch is connected to the output conductor 21A and the tone generator which delivers the highest pitch is connected to the output conductor2lD. Thus the output conductors 21A to 21D are supplied with tone signals in: the order of pitches. I

In FIG. 2B, thekey switches of each group are suc-- cessively connected in series in the opposite direction to those of FIG. 2A. The movable contacts of the four key switches actuated by the keys of lowest pitch on the extreme left-hand side are connected to the output conductors 21A to 21D, which are, in this case, supplied with tone signals in the reverse order of pitches to those of FIG. 2A.

In FIG. 2C, four groups 40A, 40B, 40C and 40D of key switches are separated into two pairs of 40A-40B and 40C-40D. In the first pair of 40A40B, the key switches are connected in series in the same direction as in FIG. 2A. In the second pair of 40C-40D, however, key switches are connected in series in the reverse direction to those of the first pair of MIA-40B, that is, in the same direction as in FIG. 2B. The idle normally open fixed contacts of the key switches of the lower groups 40B and 40D of the first and second pairs are connected to the corresponding tone generators. The movable contacts of the two key switches of the first pair of MIA-40B actuated by the keys disposed on the extreme right-hand side are connected to the output conductors 21A and 21B. The movable contacts of the key switches actuated by the keys of the second pair of 40C 40Ddisposed on the extreme left'hand side are connected to the output conductors 21Cand 21D. Accordingly, the output conductors 21A and 21B are supplied with tone signals in the same order of pitches as those of FIG. 2A and the output conductors 21C and 21D are supplied with tone signals in the same order of pitches as those of FIG. 2B.

The output conductors 21A to 21D of the second keyer 16 are connected, if required, to the tone color 7 selector 22. In FIG. 3A illustrating an example of the vided into two pairs of 21A21B and 21C-21D. Be-

tween the output conductors 21A and 21B of the first pair are connected at first potentiometer 44A, a second potentiometer 44B in reverse parallel to the first potentiometer'44A. The slidable arms of the first and second potentiometers 44A and 44B are connected to the tone coloring filters 23A and 238 respectively. Between the output conductors 21C and 21D are connected third and fourth potentiometers 44C and 44D with the same relationship as between the first and second potentiometers 44A and 448. The slidable arms of the third and fourth potentiometers 44C and 44D are connected to the tone coloring filters 23C and 23D respectively. The slidable arms of the respective pairs of the potentiometers may be ganged to each other as shown by dashed lines.

In FIG. 38, it will be apparent that where the slidable arms of the potentiometers'44A and 44B are brought to an intennediate position therebetween, then tone signals conducted through'the output conductors 21A and 21B are uniformly introduced into the tone color 2 ing filters 23A and 238. Where the slidable arms are at the upper end of the potentiometers 44A and 448, then tone signals conducted through the output conductor 21A are supplied to the tone coloring filter 23A in a maximum amount and to the tone coloring filter 23B in a minimum amount. Conversely, tone signals conducted through the output conductor 21B are supplied: to the tone coloring filter 23B in a maximum amount and to the tone coloringfilter 23A in a minimum amount. Where the slidable arms are at the lower end of the potentiometers 44A and 448, then there result the conditions opposite to those described above. Thus the level of tone signals delivered from the tone coloring filters 23A to 23D. In this case, output from the tone coloring filters 23A to 23D are supplied to asingle level control means or variable resistor 48' through fixed resistors 46A to 46D so as to be jointly subjected to level control.

FIG. 48 illustrates the case where the tone .coloring filters 23A to 231) are made'changeable infreq'uency characteristics by variable resistors 50At'o 50D respectively. This arrangement enables a player to impart freely changeable tone colors to tone signals supplied to the tone coloring filters 23A to 23D by varying their frequency characteristcs. Means for changing the frequency characteristics of the filters may be variable in ductors or capacitors besides the variable resistors 50A to 50D.

FIG. 5 is an orchestral effect producing system according to another embodiment of this invention which is intended to produce at the output conductors 2 lA to 21D of the second keyer 16 tone signals in accordance with notes constituting a chord played on the second keyboard 12. To this end, the second keyer 16 comprises a chord detector 52 which determines the type of a chord judging from the key switches actuated and generates outputs for detecting the chord notes, and first to fourth gate groups 54A to 54D which are supplied with tone signals representing the chord notes and enabled by outputs from the chord detector 52. The

chord detector 52 includes, as shown in FIG. 6, a first matrix 54A for generating a first output to detect the first and second notes or the root and fifth notes which are two main notes constituting a chord; a second matrix 548 for generating a second output to detect a third note, that is, either a major or minor third note; and a third matrix 54C for generating a third output to detect a fourth note, that is, either a minor seventh note or major sixth note. 7

In FIG. 6, a group of chord detector key switches is designated by a reference numeral 56, the group including at least twelve key switches 56A to 56L respectively actuated by twelve keys within one octave of the second keyboard 12. Key switches 56A to 56L are commonly connected to twelve column conductors of the first to third matrixes 54A to 54C. Column conductors of the first matrix 54A (also those of the second and third matrixes 54B and 54C) areconnected to the positive terminal (+12V) of a source respectively through resistors r. Twelve rows or output conductors of the first matrix 54A are grounded, respectively, through resistorsR. The first matrix 54A functions to detect the root andfifth notes of a chord. There are connected diodes D, in the forward direction with respect to the source voltage between the upper-most output conductor for detecting the chord [C] and two column conductors connected to the key switches 56A and 56H actuated by the keys of the second keyboard or chord keyboard, the keys corresponding to notes C and G, that is the root and fifth notes of chord [C]. In the same manner, diodes D, are connected between another one of the output conductors and two columnconductors for the purposeof detecting the root and ductor of the first matrix 54A. In the same. manner,

fifth notes in accordance with the type of the chord to be played. 1

The output conductors of the first matrix 54A are connected to corresponding output conductors of the secondmatrix 54B'through diodes D and D which are connected in series opposition as shown. The positiveterminal (+l 2V) of the source is connected to the junctures between diodes D and D or to the anode electrodes of these diodes-D and D respectively, through resistors R. The upper-most output conductor of the second matrix 548 is used to detect the major third note E contained inchord [Cl and there is connected a diode D between'this output conductor and the col umn conductor connected to the key switch 56E actuated by a key of the chord keyboard, corresponding to the note E. I

To detect D whichis the minor third note of chord' [c l'comprised'by notes C, D andG, there is connected a diode D ofthe polarity shown in the drawing between the juncture between diodes D and D which are connected to the lower-most output conductor of the second matrix 543 and the upper-most output condiode D1, is'connectedbetween the lower-most output conductor of the secondmatrix 54B and the column conductor connected to the key switch 56D actuated by a switch correspondingto-note D g Output conductors of the first matrix- 54A arealso con-nected to corresponding output conductors of the third matrix 54C respectively through diodes D and D connected in series opposition. The junctures between diodes D; and D that is the anode electrodes of these diodes are connected to'the positive terminal (+1 2V of the source through respective resistorsR'. The upper-most output conductor of the third matrix 54C is used to detect A i.g., the minor seventh note of chord [C comprised by notes C, E and A and there is connected a diode D between this output conductor and a column conductor connected to the key switch 56K which is actuated by a key corresponding to note A Furthermore, in order to detect-the note A, that is the major sixth note of chord [C comprised by notes C, E, G and A, there is connected a diode D, having a polarity as shown between the juncture between diodes D and D connected to the lowermost output conductor of the third matrix 54C and the uppermost output conductor of the first matrix 54A. There is connected a diode D between the lower-most output conductor of the third matrix 54C and a column conductor connected to the key switch 56] actuated by a key' corresponding to note A. Outputs generated on respective output conductors of the first, second and third matrixes 54A, 54B and 54C appear onoutput terminals 0 0: and 03 I v I I While the construction of the chorddetector matrix 52 shown in FIG. 2 has been described-with respect to the chord alone related'to chord [Clitwill'be clear to those skilled in the art that the construction for other chords is similar to that described.

The operation of the chord detector matrix will be de-scribed hereunder. The resistance 'values'of various resistors are shown by a relationship: 7 i I Y I R" R r Where all key switches 56A, 56H 56E and 56K are opened, in other words, where keys corresponding to notes C, G, E and A are not depressed, voltages substantially equal to the source voltage (+l2V) will appear on output terminals 0,, O and of respective matrixes 54A, 54B and 54C. Similar voltages will be obtained when onlyone of the key switches 54A, 54H,

54B and 54K is closed.

When key switches 56A and 56H are closed concurthe root note and fifth noteof the played chord. can be detected. Where key'switch 56E is'closed while the-key switches 56A and 56H are held closed, a voltage having the same level as that appearing on terminal 0 will appear on the output terminal 0 of the second matrix 543. In the same manner, closure of key switch 56K provides an output voltage on terminal 0 of the third matrix 54C having the same level as that on terminal 0 Thus, in the case of chords [C], [C,,,], [C,] and [C containing C ang G as the root and fifth notes, closure of the key switches 56A and 56H produces a control output (negative spike from the +l2V level) on terminal O connected to the upper-most output conductor of the first matrix 54A. In the case of a chord containing note E in addition to notes C and G, closure of the key switch 56E will produce a control output on terminal 0 connected to the upper-most output conductor of the second matrix 54B. In the case of a chord containing note A closure of the key switch 56K produces a control output on terminal 0 connected to the uppermost output conductor ofthe third matrix 54C.

From the foregoing description, it will be evident that the second and third matrixes 54B and 54C produce no defected outputs at the output terminals 0 and O insofar as the first matrix 54A produces no detected outputs at the output terminal 0,. Thus, the second and third matrixes 54B and 54C of the chord detector matrix 52 depend upon the operation of the first matrix 54A.

FIG. 7 indicates the detailed relationship of the chord detector, gate groups and tone generators. The output terminal 0 (corresponding to note A of the third matrix 54C is connected to a gate 54A] coupled with the tone generator of note A" included in the gate group 54A, and the other output terminal (corresponding to note B) of the third matrix 54C is connected to the other gate 54A2, coupled with the tone generator of note B. Other output terminals of the third matrix 54C are, though not shown, coupled with corresponding gates included in the gate group 54A. Outputs from the gates 54A] and 54A2 are coupled to the tone coloring filter 23A through the output conductor 21A.

The output terminal 0 (corresponding'to notes C ang G) of the first matrix 54A is connected to gate 54B] coupled with the tone generator of the note C included in the gate group 548 as well as to a gate 54Cl coupled with the tone generator of the note G includedin the gate group 54C. The outer output terminal (corresponding to note C of the first matrix 54A is connected to gates 5482 and 54C2. Outputs from the gates 5481, 5482 of the gate group 543 are connected to the filter 238 through the output conductor 21B and outputs from the gates 54Cl, 54C2 to the filter 23C through the conductor 21C. The output terminal 0,

(corresponding to note E) of the second matrix 548 is connected to a gate 54D1 coupled with the tone generator of the note E included in the gate group 54D. The other output terminal (corresponding to note F) of the second matrix 548 is connected to a gate 54D2. Outputs from the gates 54D], 54D2 of the gate group 54D are connected to the filter 23D through the output conductor 21D. Obviously, the arrangements of FIGS. 3A, 38, 4A and 48 can be equally used with the embodiment of FIG. 5.

Referring to FIG. 8 representing an orchestral effect producing system according to still another embodiment of this invention, reference numeral'60 represents 1 a key controlled source of variable voltage for producing at output conductors 62A to 620 voltages corresponding to notes of the operated keys of the second keyboard 12. The output conductors 62A to 62D are connected to voltage controlled variable frequency oscillators 64A to 64D respectively which in turn are coupled to the reproducing means through the corresponding tone colouring filters 23A to 23D.

.The key controlled variable voltage source 60 may include the key'switch arrangements shown in FIGS. 2A, 2B and 2C. FIG. 9 illustrates the variable voltage source 60 using the key switch arrangement of FIG. 2A.This source inlcudes key switch groups 66A to 66D arranged in the same manner as the groups 40A to 40D of serially connected key switches shown in FIG. 2A. The normally open fixed contacts of the key switches of the lowermost group 66D are connected to predetermined different magnitude potential points respectively. In this case, resistors 68 may be connected between the adjacent ones of the normally open connects of the key switches and across all these resistors 68 thus connected in series there may be connected a D.C.

source or battery 70. Where, under the abovementioned arrangement, there are operated a plurality of keys on the second keyboard 12, then the output conductors 62A to 62D are obviously impressed with different D.C. voltages in the order of magnitude. The D.C. control voltages on the output conductors 62A to 62D are applied to the voltage controlled variable frequency oscillators 64A to 64D which, upon receipt of the voltages, generate tone signals having frequencies corresponding to the magnitudes of the voltages. The oscillators may include, for example,lastable multivi brators. The control voltages produced on the conductors 62A to 62D in response to key operation are predetermined to have such magnitudes as to cause the voltage controlled variable frequency oscillators to generate fre-quencies corresponding to the notes of the operated keys.

What is claimed is: 1. An electronic; musical instrument comprising: a first keyboard means having a plurality of keys for a melody performance; 7 v I, I a second keyboard means having a plurality of keys for accompaniment to the melody performance, some of said keys being generally-operated simultaneously; I aplurality of tone generators for generating tone sig nals for the melody performance and accompaniment thereto; a

first keyer means coupled to said tone generators and first keyboard to derive tone signals from said tone generators upon key operation;

' acteristics for providing said tone signals with different tone colors; and-1 sound reproducing means connectedto said first and second tone coloring filters. v

2. The electronic musical instrument according to claim 1 further comprising tone color selecting emans disposed between said second keyer means and second time coloring filter means for selectively connecting said output conductors of said second keyer means to said second plural tone coloring filter means.

3. The electronic musical instrument according to claim 2 wherein said tone color selecting means includes as many multithrow switches as said output conductors.

4. The electronic musical instrument according to claim 1 wherein said output conductors include at least first and second conductors producing thereon first and secondtone signals respectively, and said second plural tone coloring filter means include at least first and second tone coloring filters, and further including means disposed between said first and second conductors and said first and second tone coloring filters for reciprocally varying a ratio of amount of said first tone signal supplied to said first filter to that of said first signal supplied to said second filter and a ratio of amount of said second tone signal supplied to said first filter to that of said second signal supplied to said second filter.

5. The electronic musical instrument according to claim 4 wherein said sound reproducing means comprises first and second potentiometers each having a slidable arm, said first potentiometer being connected between said first and second output conductors, with its slidable arm connected to said first tone coloring filter means, and said second potentiometer being connected between said first and second output conductors in reverse'paralle'l to said first potentiometer with its slidable arm connected to said second tone coloring filter means.

6. The electronic musical instrument according to claim 5 wherein said slidable arms of said first and second potentiometers are ganged with each other.

7. The electronic musical instrument according to claim 1 further comprising variable means disposed between said sound reproducing means and said first and filter means.

9. The electronic musical instrument according to claim 1 further comprising means for controlling the level of outputs from said second plural tone coloring filter means.

10. The electronic musical instrument according to claim 1 further comprising a plurality of means for individually controlling the levels of outputs from said sec ond plural tone coloring filter means.

11. The electronic musical instrument according to claim 1 wherein said second plural tone coloring'filter means each include a manually variable means for varying the frequency. characteristics thereof.

' 12. The electronic musical instrument according to claim 1 wherein said second keyer includes a plurality of groups of serially connected key switches havingnormally open andnorma llyclosed contacts and movable contacts actuated by the keys of said second keyboard, said normally open contacts and normally closed contacts of said key switches of the adjacent groups actuated by the same key being connected in turn, said normally open fixed contacts of those key switches of the outermost group which are not connected to said normally closed fixed contacts of the key switches being connected to'said corresponding tone generators, and said movable contacts of said key switches at the extreme right end of the respective groups being connected to said output conductors.

13. The electronic muSical instrument according to claim 1 wherein said second keyer comprises a first plurality of groups of serially connected key switches whose movable contacts and normally open and nor mally closed contacts are actuatedby the keys of the second keyboard and a second plurality of groups of key switches serially connected in the opposite direction to those of said first plurality of groups, the normally open fixed contacts and normally closed fixed contacts of those adjacent key switches of said first and second pluralities of groups which are actuated by the same key being connected in turn, the normally open fixed contacts of those key switches of the outermost ones of said first and second pluralities of groups which are not connected to the normally closed fixed contacts of the key switches being connected to the corresponding tone generators and the movable contacts of those key switches of said first plurality of groups which are disposed at one extreme end and the movable contacts of those key switches of said second plurality of groups which are positioned at the opposite extreme end being connected to the output conductors.

14. The electronic musical instrument according to claim 1 wherein said second keyer comprises key switches actuated by the keys of said secondkeyboard; and further including a chord detector for determining the'type of a chord played on said second keyboard from a combination of the key switches actuated by key operation and generating detecting outputs corre-' sponding to the notes of said chord; and a pluralityfof gates connected between said tone'generators and second tone coloring filter means for receiving tone signals corresponding. to the notes of said chord, said gates being enabled by corresponding detecting outputs from said chord detector.

15. The electronic musical instrument according to claim- 14 wherein said chord detector comprises first, second and third matrix means associated with said key switches actuated by the keys of said second keyboard, said first matrix means being adapted to generate a first output for detecting the first and second main notes of a chord upon actuation of said key switches corresponding to said notes, said second matrix means being adapted to produce a second output for detecting the third note of said chord upon actuation of the key switch corresponding to said note in response to the generation of said first detection output, and said third matrix means being adapted to produce a third output for detecting the fourth note of said chord upon actuation of the key switch corresponding to said note in response to the generation of said first detection output. 16. The electronic musical instrument according to claim 15 wherein said first and second notes of said chord represent root and fifth notes, said third note a major or minor third note and said fourth note a minor seventh or major sixth note. i

17. An electronic musical instrument comprising: a keyboard having a plurality of keys, some of which are generally operated at the same time; a key controlled variable voltage source means coupled to and actuated by said keyboard and being provided with a plurality of output conductors, said key controlled variable voltage source means supa plurality of tone coloring filter means with different frequency characteristics respectively connected to said respective voltage controlled oscillating means so as to convert respective output signals from said oscillating means to tone signals bearing different tone colors; and

sound reproducing means connected to said tone coloring filter means.

18. The electronic musical instrument according to claim 17 wherein said key controlled variable voltage source means is actuated by the keys of said keyboard and comprises serially connected key switches having movable contacts and normally openvan d closed fixed "contacts arranged in as many' groups as said output conductors, the normally open contacts and normally closed contacts of those key switches of the adjacent groups which are actuated by the same key being connected in turn, the normally open contacts of the key switches of at least one group being connected to different magnitude potential points corresponding to the notes of the keys, and the movable contacts of those key switches of the respective groups which are disposed atone extreme end being connected to said output conductors.

19. The electronic musical instrument according to claim 18 wherein the normally open contacts of the key switches connected to D.C. sources having different magnitudes are connected to each other by serially connected resistors which in turn are collectively connected to a D.C. source. 3 i

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Peten t No. '3 ,749 ,807 Dated I y 31 1973' Inve ntor(s) Takeshi ADACHI I It is certified that error appears in the above-identifidpatent and that said Letters Patent are hereby corrected as shown below:

Page 1 in the heading of the patent, add the following Assignmentgdata:

--[73] A's sign ee: NIPPON GAKKI sETzo KABUSHIKI KAISHA Shizuoka-keh, Japan- Column 9 line 3, change "'generator to generators Column 9, line 17, change "emans" to -means--; I Column 10, I line 26, change "musical" to mi1 sical---.

Signed and sealed this l9th day ofMarch 1974 (SEAL) Attes t':

EDWARD M.FLETCHER,JR

a .e C MARS'HALL DA NN Attestlng Offlcer Commissionerof-Patents FORM P0 1 050 10-69) 1 USCOMM-DC 60376-P69 U-S. GOVEINMEF IT PRIN ING OFIICE Z l," O3i-l,,

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION ,Patent No. 3,749,807 Dated July 31, 1973 Inventor( Takeshi ADACHI It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Page 1 in the heading of the patent, add the following Assignment data:

[73] As signee: NIPPON GAKKI SEI'ZO KABUSHIKI KAISHA Shizuoka-ken, Japan-;

Column 9, line 3, change "generator" to -generators-; Column 9, line 17, change "emans" to -means--;

Column 10, line 26, change "musical" to musical-.

Signed and sealed this l 9th day of March 1974.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. C. MARSHALL DANN Attestlng Officer Commissioner of Patents F ORM PC3-1050 (10-69) USCOMM'DC 60378-P69 US. GOVERNMENT PRINTING OFFICE: (969 0-366-38L 

1. An electronic musical instrument comprising: a first keyboard means having a plurality of keys for a melody performance; a second keyboard means having a plurality of keys for accompaniment to the melody performance, some of said keys being generally operated simultaneously; a plurality of tone generators for generating tone signals for the melody performance and accompaniment thereto; first keyer means coupled to said tone generators and first keyboard to derive tone signals from said tone generators upon key operation; first tone coloring filter means connected to said first keyer means; second keyer means coupled to said tone generator and said second keyboard and having output conductors for producing at said respective output conductors respective different tone signals corresponding to respective different ones of the simultaneously operated keys; a plurality of second tone coloring filter means connected to said output conductors of said second keyer means and having different frequency characteristics for providing said tone signals with different tone colors; and sound reproducing means connected to said first and second tone coloring filters.
 2. The electronic musical instrument according to claim 1 further comprising tone color selecting emans disposed between said second keyer means and second tone coloring filter means for selectively connecting said output conductors of said second keyer means to said second plural tone coloring filter means.
 3. The electronic musical instrument according to claim 2 wherein said tone color selecting means includes as many multithrow switches as said output conductors.
 4. The electronic musical instrument according to claim 1 wherein said output conductors include at least first and second conductors producing thereon first and second tone signals respectively, and said second plural tone coloring filter means include at least first and second tone coloring filters, and further including means disposed between said first and second conductors and said first and second tone coloring filters for reciprocally varying a ratio of amount of said first tone signal supplied to said first filter to that of said first signal supplied to said second filter and a ratio of amount of said second tone signal supplied to said first filter to that of said second signal supplied to said second filter.
 5. The electronic musical instrument according to claim 4 wherein said sound reproducing means comprises first and second potentiometers each having a slidable arm, said first potentiometer being connected between said first and second output conductors, with its slidable arm connected to said first toNe coloring filter means, and said second potentiometer being connected between said first and second output conductors in reverse parallel to said first potentiometer with its slidable arm connected to said second tone coloring filter means.
 6. The electronic musical instrument according to claim 5 wherein said slidable arms of said first and second potentiometers are ganged with each other.
 7. The electronic musical instrument according to claim 1 further comprising variable means disposed between said sound reproducing means and said first and second tone coloring filter means for supplying said sound reproducing means with outputs from the first and second tone coloring filters in interconnected relationship.
 8. The electronic musical instrument according to claim 7 wherein said variable means includes a potentiometer having a slidable arm connected to said sound reproducing means with both ends of said potentiometer connected to said first and second tone coloring filter means.
 9. The electronic musical instrument according to claim 1 further comprising means for controlling the level of outputs from said second plural tone coloring filter means.
 10. The electronic musical instrument according to claim 1 further comprising a plurality of means for individually controlling the levels of outputs from said second plural tone coloring filter means.
 11. The electronic musical instrument according to claim 1 wherein said second plural tone coloring filter means each include a manually variable means for varying the frequency characteristics thereof.
 12. The electronic musical instrument according to claim 1 wherein said second keyer includes a plurality of groups of serially connected key switches having normally open and normally closed contacts and movable contacts actuated by the keys of said second keyboard, said normally open contacts and normally closed contacts of said key switches of the adjacent groups actuated by the same key being connected in turn, said normally open fixed contacts of those key switches of the outermost group which are not connected to said normally closed fixed contacts of the key switches being connected to said corresponding tone generators, and said movable contacts of said key switches at the extreme right end of the respective groups being connected to said output conductors.
 13. The electronic muSical instrument according to claim 1 wherein said second keyer comprises a first plurality of groups of serially connected key switches whose movable contacts and normally open and normally closed contacts are actuated by the keys of the second keyboard and a second plurality of groups of key switches serially connected in the opposite direction to those of said first plurality of groups, the normally open fixed contacts and normally closed fixed contacts of those adjacent key switches of said first and second pluralities of groups which are actuated by the same key being connected in turn, the normally open fixed contacts of those key switches of the outermost ones of said first and second pluralities of groups which are not connected to the normally closed fixed contacts of the key switches being connected to the corresponding tone generators and the movable contacts of those key switches of said first plurality of groups which are disposed at one extreme end and the movable contacts of those key switches of said second plurality of groups which are positioned at the opposite extreme end being connected to the output conductors.
 14. The electronic musical instrument according to claim 1 wherein said second keyer comprises key switches actuated by the keys of said second keyboard; and further including a chord detector for determining the type of a chord played on said second keyboard from a combination of the key switches actuated by key operation and generating detecting outputs corresponding to the notes of said chord; and a plurality of gates connected between said tone generators and second tone coloring filter meAns for receiving tone signals corresponding to the notes of said chord, said gates being enabled by corresponding detecting outputs from said chord detector.
 15. The electronic musical instrument according to claim 14 wherein said chord detector comprises first, second and third matrix means associated with said key switches actuated by the keys of said second keyboard, said first matrix means being adapted to generate a first output for detecting the first and second main notes of a chord upon actuation of said key switches corresponding to said notes, said second matrix means being adapted to produce a second output for detecting the third note of said chord upon actuation of the key switch corresponding to said note in response to the generation of said first detection output, and said third matrix means being adapted to produce a third output for detecting the fourth note of said chord upon actuation of the key switch corresponding to said note in response to the generation of said first detection output.
 16. The electronic musical instrument according to claim 15 wherein said first and second notes of said chord represent root and fifth notes, said third note a major or minor third note and said fourth note a minor seventh or major sixth note.
 17. An electronic musical instrument comprising: a keyboard having a plurality of keys, some of which are generally operated at the same time; a key controlled variable voltage source means coupled to and actuated by said keyboard and being provided with a plurality of output conductors, said key controlled variable voltage source means supplying said respective output conductors with respective different control voltages of magnitudes respectively corresponding to the different notes of the simultaneously operated keys; a plurality of voltage controlled oscillating means respectively connected to said respective output conductors of said key controlled variable voltage source means and adapted to have their frequency of oscillation varied in accordance with the magnitude of control voltage impressed; a plurality of tone coloring filter means with different frequency characteristics respectively connected to said respective voltage controlled oscillating means so as to convert respective output signals from said oscillating means to tone signals bearing different tone colors; and sound reproducing means connected to said tone coloring filter means.
 18. The electronic musical instrument according to claim 17 wherein said key controlled variable voltage source means is actuated by the keys of said keyboard and comprises serially connected key switches having movable contacts and normally open and closed fixed contacts arranged in as many groups as said output conductors, the normally open contacts and normally closed contacts of those key switches of the adjacent groups which are actuated by the same key being connected in turn, the normally open contacts of the key switches of at least one group being connected to different magnitude potential points corresponding to the notes of the keys, and the movable contacts of those key switches of the respective groups which are disposed at one extreme end being connected to said output conductors.
 19. The electronic musical instrument according to claim 18 wherein the normally open contacts of the key switches connected to D.C. sources having different magnitudes are connected to each other by serially connected resistors which in turn are collectively connected to a D.C. source. 